Nucleobase transporter

Hyde, R. J., et al. The ENT family of eukaryote nucleoside and nucleobase transporters recent advances in the investigation of structure/function... 

Lu, X., et al. Correlation of nucleoside and nucleobase transporter gene expression with antimetabolite drug cytotoxicity. J. Exp. Ther. Oncol. 2002,... 

Pastor-Anglada, M., Baldwin, S.A. Recent advanceses in the molecular biology and physiology of nucleoside and nucleobase transporters, DDR 2001, 52, 431-437. 

Plageman, P. G. W., R. M. Woehlheuter, and C. Woffendin, Nucleoside and nucleobase transport in animal cells. Biochem. Biophys. Acta 947 405-443, 1988. Reviews the field in detail. 

Biochemistry, Physiology, and Pharmacology of Nucleoside and Nucleobase Transporters... 

Kato, R., Maeda, T, Akaike, T, and Tamai, I. (2006) Characterization of novel Na+-dependent nucleobase transport systems at the blood-testis barrier. American Journal of Physiology. Endocrinology and Metabolism, 290 (5), E968-E975. 

SLC23 (2) Nucleobase transporters SVCT Brain, eye, intestine, kidney, liver... 

Al-Salabi MI, Wallace LJM, de Koning HP. A Leishmania major nucleobase transporter responsible for allopurinol uptake is a functional homolog of the Trypanosoma brucei H2 transporter. Mol Pharmacol 2003 63 814-820. 

Sanchez M, Tryon R, Vasudevan G et al. Functional oepression and characterisation of a purine nucleobase transporter gene from Leishmania major. Mol Membrane Biol 2004 21 11-18. 

The presence of a de novo synthesis pathway implies that pyrimidine sahmge may be functionally redundant and potentially less critical to the nutrition of the parasite than purine acquisition. Similar to purine salvage, pyrimidine salvage is initiated by the translocation of pyrimidine nucleosides or nucleobases across the parasite cell membrane via specific transporters. As described earlier, leishmanial NTl is responsible for the transport of pyrimidine nucleosides. The sole pyrimidine nucleobase transport activity in Leidrmania has been dtantctetized biochemically in L. major (LmUl) and shown to rect nize uracil exdusively and with hi affinity, but has not yet been doned. 

Yao SYM, Ng AML, Vickers MF et al. Functional and molecular characterization of nucleobase transport by recombinant human and rat equilibrative nucleoside transporters 1 and 2. J Biol Chem 2002 277 24938-24948. 

Pap eorgiou IG, Yakob L, Al Salabi MI et al. Identification of the first pyrimidine nucleobase transporter in Leishmania Similarities with the Trypanosoma brucei U1 transporter and antileishmanial activity of uracil analogues. Parasitology 2005 130(Pt 3) 275-283. 

The synthetic pirimidine, 5-fluouracil (5-FU), is used in the treatment of a variety of epithelial tumors including, colorectal, breast cancer, ovarian, head, and neck cancers. 5-FU enters tumor cells by a facilitated nucleobase transporter and is converted into active metabolites (5 -fluoro-2 -deoxyuridine) by a complex metabolic pathway that interferes with both DNA and RNA syntheses. Of particular interest is the conversion of 5-FU to 5 -fluoro-2 -deoxyur-idine (5-FUdR) and subsequent phosphorylation by thymidine kinase to the active metabolite 5 -fluoro-2 -DUMP (5-FdUMP). Unfortunately, the response rate of patients receiving 5-FU-based chemotherapy is relatively poor, varying between 10 and 30%. To further evaluate, 5-FU labeled with F (5- FU) has been used in PET studies to understand the factors behind this strong interindividual variability. As 5- FU is biochemically identical to 5-FU, PET has been used for quantitative pharmacokinetic measurements of 5- FU in human and animal models. 

Ortiz D, Sanchez MA, Koch HP et al (2009) An acid-activated nucleobase transporter from Leishmania major. J Biol Chem 284 16164—16169... 

Faaland, C. A. Race, J. E. Ricken, G. Warner, R J. Williams, W. J. Holtzman, E. J. 1998. Molecular characterization of two novel transporters from human and mouse kidney and from LLC-RKl cells reveals a novel conserved family that is homologous to bacterial and AspeigiUus nucleobase transporters. Biochimica Biophysica Acta. 1442(2-3) 353-360. 

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